Biodegradable cleaning compound



United States Patent 3,360,471 BIODEGRADABLE CLEANING COMPOUND Bohdan Kwiatkowski, Chicago, Ill., assignor, by mesne assignments, to Sterling Drug Inc., a corporation of Delaware No Drawing. Filed Apr. 18, 1963, Ser. No. 273,833 5 Claims. (Cl. 252-114) This invention relates to a biodegradable cleaning compound, and more particularly to a mobile, water soluble, biodegradable cleaning compound concentrate base for forming such a cleaning compound.

Various liquid cleaning compound concentrates are commercially available. These concentrates are generally aqueous solutions of various combinations of soaps, detergents, and soap builders, along with suitable amounts of dyes and perfumes to form a desired product. The concentrates are mixed with various amounts of Waters to form cleaning compounds. In most instances, soap based cleaning compound concentrates are produced in the same concentration as sold commercially, and contain a relatively large amount of water, i.e., considerably more than about 50 percent by weight. The large amount of water in most liquid cleaning compounds greatly increase the costs of shipping and handling of these compounds.

In general, it has not been feasible to manufacture and ship a soap based cleaning compound concentrate base containing very small amounts of water due to the viscous and gelling nature of conventional low water cleaning compound concentrate bases which makes it very difficult and uneconomical to handle these bases. In this connection, low water cleaning concentrate bases are sometimes difficult to mix with Water without violent agitation, and in most instances, it is necessary to apply heat during the mixing of the concentrate bases with water in order to effect the dissolving of the bases in water.

Crude tall oil, a byproduct of the sulphate process for treating Wood in the preparation of cellulose, contains a mixture of rosin acids and fatty acids. Tall oil is fractionated to separate the fatty acids from the rosin acids. The fatty acids present in fractionated tall oil are mainly oleic acid and linoleic acid, with lesser amounts of linolenic acid, saturated acids and rosin acids. Tall oil fatty acds are a desirable raw material for the manufacture of soaps and cleaning compounds due to its relatively low cost. As used through this specification, the term tall oil isintended to mean tall oil fatty acids. Tall oil may be reacted by saponification with lye, e.g., sodium or potassium hydroxide, to form soluble tall oil soaps. The tall oil saponification is normally carried out in the presence of Water, forming an aqueous tall oil soap solution containing a relatively large amount of water. Tall oil soaps have heretofore been employed in liquid cleaning compounds, but have included a relatively large amount of water associated therewith.

The various commercially available liquid cleaning compound concentrates normally contain, in addition to the soap or detergent, various soap builders which increase the cleaning power of the cleaning compound. The soap builders increase the cleaning action of the cleaning compound. Various sodium phosphates are conventionally employed as soap builders, sodium tripolyphosphate being a particular soap builder normally employed in cleaning compounds.

Many of the currently available detergents and liquid cleaning compounds are not biodegradable, that is, they are not broken down by the bacterial and enzymatic processes that occur in conventional sewage systems. This is a particularly undesirable characteristic of these compounds since, in many instances, the outlet from the sewage system is into a river or lake. If the cleaning compound is not broken down in the sewage system it may cause pollution and foaming of the water of the river or lake. If the cleaning compound is biodegradable, it will be broken down by the sewage system and can safely be employed, even in large amounts, without causing pollution.

It is the principal object of the present invention to provide an improved biodegradable cleaning compound. Another object is to provide an improved concentrate base of liquid cleaning compound which is readily soluble and dispersible in water. A further object is to provide a concentrate base for a liquid cleaning compound which con tains a relatively low concentration of water and which is mobile at ambient temperatures. A still further object is to provide a concentrate base for a liquid cleaning compound which can be manufactured without supplying external heat thereto. Yet another object is to provide a method for manufacturing a concentrate base for a liquid cleaning compound which has a relatively low water concentration and which is mobile at ambient temperatures.

These and other objects and advantages of the present invention are more particularly set forth in the following detailed description.

In general, the present invention comprises a liquid cleaning compound concentrate base which is readily soluble and dispersible in water and which contains substantially less amounts of water than conventional cleaning compounds; and the method of making such a concentrate base. The concentrate base comprises at least about 55 percent by weight of a soap dissolved in a suitable solvent. The soap is formed by the reaction between a soap forming fatty acid and lye. The lye is present in an amount so that the amount of free alkaline matter of the concentrate base is less than 0.05 percent by Weight, calculated as potassium hydroxide, and so that the free fatty acid content of the concentrate base is less than 0.05 percent by Weight. The concentrate base may be mixed with soap builders, sequestering agents, and suitable amounts of perfume and dye to form a cleaning compound concentrate which can be further diluted with water to form a regular liquid cleaning solution.

More specifically, the present invention relates to a method of making a concentrate base for a liquid cleaning solution which comprises dissolving tall oil in a tripropylene glycol methyl ether solvent which is free from water and reacting the tall oil dissolved in the solvent with lye to form tall oil soaps. The solvent is preferably employed in a ratio of solvent to soap of about 1 to 3.5 by weight. Beta-terpineol is added in an amount of about 1 percent to 5 percent by Weight of the concentrate base as a viscosity reducing agent. Such viscosity reduction improves the handling characteristics of the base. The amount of lye added to the tall oil is controlled so that the amount of free alkaline matter in the concentrate base is less than 0.05 percent by weight, calculated as potassium hydroxide, and so that the amount of free fatty acid present is less than 0.05 percent by weight of the concentrate base.

The cleaning compound concentrate base may be formed from any suitable fatty acid or combination of fatty acids normally used in the production of soap and which undergoes a saponification reaction, e.g., stearic acid, oleic acid, etc. Commercial fractionated tall oil includes various fatty acids which are particularly desirable for use in the preparation of the cleaning compound concentrate base due to its low cost. However, the use of other oils and fatty acids are also contemplated.

To provide a low water soap containing liquid cleaning compound concentrate base of this invention, it is necessary to manufacture the soap in a substantially nonaqueous medium. Since water is a byproduct of the saponification reaction, the concentrate base necessarily contains some water. Additionally, some Water is present in the lye solution. However, it has been discovered that the amount of water present in a cleaning compound concentrate base can be kept at a very low level without greatly increasing the viscosity of the concentrate base if a suitable solvent for the fatty compound, e.g., tall oil, is selected. The solvent for the tall oil or other fatty acid desirably has the characteristics of being soluble in water, as well as being miscible with other solvents such as acetone, alcohol, glycol, etc, and should provide a medium in which the reaction between the tall oil and lye may take place.,The solvent must be able to withstand the heat generated by the saponification reaction and should be. miscible with any viscosity reducing agent that may be added to the concentrate base.

A suitable solvent for the tall oil soap concentrate base is tripropylene glycol methyl ether. Tripropylene glycol methyl ether is soluble in water, and miscible with acetone, glycol, hydrocarbons, etc., and provides a suitable medium in which the reaction between the lye and the tall oil can take place. Other ethers similar to tripropylene glycol methyl ether, or alcohols having similar characteristics, can also be employed.

It has been found that a particular ratio of solvent to soap is desired in the concentrate base to provide the desired cleaning compound. The ratio of the tripropylene glycol methyl ether to the tall oil soap in the concentrate base should preferably be about 1 to 3.5 by weight, although slight variations therefrom are contemplated. If a lesser amount of solvent is employed, it appears that there is. not sufficient medium present in which an optimum reaction between the tall oil and the lye may take place. Likewise, greater amounts of solvent do not enhance the saponification reaction or the cleaning power of the concentrate base, and merely add additional weight to the concentrate base, thereby increasing costs.

The concentrate base should preferably have less than about 0.05 percent by Weight of free alkaline matter, calculated as potassium hydroxide, and has less than 0.05 percent, by weight, of free fatty acid. These limitations give the most desirable final product which will not injure fabrics or surfaces with which it may come into contact.

It is preferred to form the concentrate base from an aqueous potassium hydroxide lye solution containing about 45 percent active potassium hydroxide. Sodium hydroxidelye may also be employed, but potassium hydroxide is preferred in that it forms more soluble soap compounds. It has been found that a 45 percent aqueous potassium lye solution provides a sufficient amount of water, when combined With the water produced by the reaction between the tall oil and the lye, and the solvent together with the viscosity reducing agent described hereinafter, to provide a mobile concentrate base at ambient temperatures Which can be easily handled, packaged and mixed with water and various soap builders to form an improved cleaning compound.

A viscosity reducing agent may also be added to the concentrate base to further reduce the'viscosity thereof. The viscosity reducing agent should desirably have the characteristics that the addition of minor amounts thereof to the concentrate base will reduce the viscosity of the base to the pointthat it is mobile at ambient temperatures to provide an easily handled concentrate base without greatly increasing the weight of the base. A preferable viscosity reducing agent is beta-terpineol. It has been found that when about 1 percent to about 5 percent by weight of the concentrate base of beta-terpineol is added to the concentrate base, the viscosity of the base is reduced to a point'where it is mobile at ambient temperatures and can be readily handled. Other viscosity reducing agents, having properties similar to beta-terpineols when added to the concentrate base in similar amounts, can also be employed.

A concentrate base for a liquid cleaning compound made in accordance with the above is mobile at room temperatures and can be shipped and handled with relative ease. The concentrate base contains at least about 55 percent tall oil soaps and preferably contains about 60 percent tall oil soaps, about 20 percent solvent and viscosity reducing agent and about 20 percent water.

The concentrate base is preferably formulated by dissolving the tall oil in the tripropylene glycol methyl ether solvent under moderate agitation in any suitable reaction vessel. Since the reaction does not require the addition of external heat, the reaction vessel need not be heated. The beta-terpineol may be added to the solvent before or after the tall oil is dissolved therein. As a matter of convenience, the beta-terpineol is added to the tripropylene glycol methyl ether before the addition of the tall oil. The aqueous lye solution is then added to the mixture of tall oil, tripropylene glycol methyl ether and betaterpineol while continuing agitation. The lye is preferably added slowly to control the temperature so as to avoid undesirable evaporation and to avoid the possibility of the reaction becoming uncontrollable. The concentrate base is desirably agitated for one-half to one hour after all the lye has been added to assure that saponification has proceeded to completion. The concentrate base may be packaged while hot or may be cooled first, as desired. The base is mobile at ambient temperatures and can be conveniently packaged using conventional equipment.

By providing a low water, mobile cleaning compound concentrate base, shipping costs are reduced by not paying for the shipment of large amounts of water.

The concentrate base may be mixed with soap builders, sequestering agents, thickening agents if necessary, water, dye and perfume to form a mobile water soluble cleaning compound concentrate.

The soap builders can be those builders conventionally employed in the soap and detergent industries. One particular soap builder composition, including sequestering agents, which has been found to be desirable is as follows:

- Percent Tetrasodium ethylene diamine tetraacetate Sodium tripolyphosphate 25 Tetrapotassium pyrophosphate 33 Trisodium phosphate monohydrate 37 Total The soap builders mixture set forth above may be mixed with water in the ratio of 1.2 pounds of the soap builder mixture to 6 pounds of water to provide a soap builder solution which has been found to provide added cleaning power when added to the concentrate base to form a cleaning compound concentrate.

Additional sequestering agents can also be added to the cleaning compound concentrate if desired.

It is generally desirable to add a thickening agent to the cleaning compound concentrate. The thickening agent increases the viscosity of the concentrate, which may become undesirably thinned due to the dilution of the concentrate base with further Water which may be additionally supplied. A suitable thickening agent is a mixture of 3 pounds of diethanol amine and 4 pounds of tall oil. Other amine and amide compounds having similar properties to the mixture of diethanol amine and tall oil can also be employed to increase the viscosity of the cleaning compound concentrate.

The preferred ingredients for the cleaning compound concentrate are as follows:

Suitable amounts of dyes and perfumes may also be added to the cleaning compound concentrate. One pound of lavender lemon perfume per 450 pounds of cleaning compound concentrate provides the concentrate with a suitable odor.

A large amount of the concentrate may be made at one time and can be stored until it is used. The concentrate has a viscosity so that it is easily handled and is readily soluble in water to form a regular cleaning compound. A cleaning compound, suitable for cleaning hard surfaces, such as walls, floors, tile, linoleum, etc., can be formed by mixing equal parts of the cleaning compound concentrate and water.

Example I A cleaning concentrate base is prepared by dissolving 95 pounds of tall oil in a mixture of 32 pounds of tripropylene glycol methyl ether and 2 pounds of betaterpineol. 41 pounds of a 45 percent aqueous potassium lye solution is then slowly added to the mixture of tall oil, tripropylene glycol methyl ether and beta-terpineol with agitation. The reaction between the tall oil and the potassium hydroxide causes the evolution of heat. The addition of the lye is controlled to avoid too rapid a tem perature rise. Agitation is continued for approximately one-half to one hour after all of the lye solution has been added. A cleaning base concentrate is obtained which contains approximately 60 percent potassium tall oil soaps, 20 percent tripropylene glycol methyl ether solvent and beta-terpineol, and 20 percent water. The concentrate base is mobile at room temperature and is easily handled.

Example 11 A liquid cleaning compound concentrate is formed from the cleaning compound concentrate base produced according to Example I by forming a mixture of 2.4 pounds of the concentrate base and 4.5 pounds of water. To the mixture of the concentrate base and water is added 0.6 pound of a thickening agent comprising a mixture of 3 pounds of diethanol amine and 4 pounds of tall oil; and 1.2 pounds of a soap builders mixture as set forth above dissolved in 6 pounds of water. One pound of a lavender lemon perfume per 450 pounds of the concentrate is also added to the concentrate.

The cleaning compound concentrate produced is mutually soluble with water to provide a cleaning compound, and a suitable cleaning compound is formed by mixing the cleaning compound concentrate with an equal amount, by weight, of water. The cleaning compound thus produced is satisfactory for normal cleaning tasks, such as those in a home or hospital, etc., and is capable of removing grease and grime from all hard surfaces such as floors, woodwork, walls, etc.

The cleaning compound produced has the desirable characteristic of being completely biodegradable, and is broken down by the bacterial organisms present in conventional sewage systems, thus reducing the pollution problems normally associated with synthetically produced detergents and cleaning compounds.

It can be seen that a liquid cleaning compound has been provided which can be formed from a mobile cleaning compound concentrate base having a relatively low water concentration by the individual consumer or institutional user. The low water concentration in the cleaning compound concentrate base results in a saving in transportation and shipping costs.

Various of the features of the present invention are set forth in the following claims.

What is claimed is:

1. A biodegradable fluid cleaning concentrate base for mixing with water comprising, at least about 55 percent by weight of a tall oil soap dissolved in a tripropylene glycol methyl ether solvent, the ratio of said solvent to said soap being about 1 to 3.5 by weight, between about one percent and about five percent by weight of said base of terpineol, the remainder of said base being substantially water, said base having less than 0.05 percent by weight of free alkaline matter calculated as potassium hydroxide.

2. A biodegradable water soluble fluid cleaning concentrate base comprising, at least about 55 percent by weight of a tall oil soap, said soap being dissolved in a tripropylene glycol methyl ether solvent, the ratio of said solvent to said soap being about 1 to 3.5 by weight, between about 1 percent and about 5 percent by weight of said base of terpineol, the remainder of said base being substantially water, said base having less than about 0.05 percent by weight of free alkaline matter calculated as potassium hydroxide and less than about 0.05 percent by weight of free fatty acid.

3. The method of manufacturing a biodegradable water soluble cleaning concentrate base for cleaning hard surfaces having a relatively low concentration of water, which method comprises the steps of dissolving tall oil in a non-aqueous mixture of tripropylene glycol methyl ether and terpineol, and adding an about 45 percent by weight active aqueous solution of potassium hydroxide to said mixture under conditions of agitation and added water and in the absence of heat to form a concentrate base, said solution being added in an amount so that said base has less than about 0.05 percent by weight of free alkaline matter calculated as potassium hydroxide and a free fatty acid concentration of less than 0.05 percent by weight, the combination of said tripropylene glycol methyl ether and said terpineol being present in an amount of about 20 percent by weight of said base, said terpineol being present in an amount of about 1 percent to 5 percent by weight of said base, whereby a liquid cleaning compound concentrate base is provided which is flowable at ambient temperature.

4. A biodegradable water soluble fluid cleaning concentrate for cleaning hard surfaces comprising, at least about 15 percent by weight of a cleaning concentrate base, at least about 7 percent by weight of alkaline phosphate soap builders, the remainder being substantially water, said base including at least about 55 percent by weight of tall oil soap dissolved in a tripropylene glycol methyl ether solvent, the ratio of said solvent to said soap being about 1 to 3.5 by weight, and between about 1 and about 5 percent by weight of said base of terpineol, said base having less than about 0.05 percent by weight of free alkaline matter calculated as potassium hydroxide.

5. A biodegradable water soluble fluid cleaning concentrate for cleaning hard surface comprising, at least about 15 percent by weight of a cleaning concentrate base, at least about 40 percent of an aqueous solution of soap builders and sequesterants selected from the group consisting of tetra sodium ethylene diamine tetra acetate, sodium tripolyphosphate, tetra potassium pyrophosphate, trisodium phosphate monohydrate and mixtures thereof, at least about 3 percent by weight of a thickening agent, said thickening agent including an amine soap of diethanol amine and tall oil, the remainder being substantially water, said base including at least about 55 percent by weight of tall oil soap dissolved in a tripropylene glycol 7 a methyl ether solvent, the ratio of said solvent to said 7 FOREIGN'PATENTS soap being about 1 to 3.5 by weight and terpineol, said 438,231 11/1935 Great Britain v.terpineol being present in an amount of about 1 percent to 5 percent by weight of said concentrate base, said base OTHER REFERENCES having less than about 0.05 percent by weight of free 5 Mellan: Industrial Solvents (2nd edition), Rheinhold alkaline matter calculated as potassium hydroxide. Publishing Corp, New York, 1950, pp. 670-671 relied on. Dow Products, Dow Chemical Co., Midland, Mich. References Cited (1962), p. 3 relied on (Form No. 160-1862). UNITED STATES PATENTS LEON D. ROSDOL, P "m E 2,073,464 3/1937 Davey 252-422 my mmme' 2,089,305 8/1937 Stickdorn 252 122 JULIUS GREENWALD, SAMUEL BLECH, 2,196,763 4/1940 Figg 252 122 Examine"- 2,901,433 8/ 1959 Spring 252--l 14 J. T. FEDIGAN, Assistant Examiner. 

1. A BIODEGRADABLE FLUID CLEANING CONCENTRATE BASE FOR MIXING WITH WATER COMPRISING, AT LEAST ABOUT 55 PERCENT BY WEIGHT OF A TALL OIL SOUP DISSOLVED IN A TRIPROPYLENE GLYCOL METHYL ETHER SOLVENT, THE RATIO OF SAID SOLVENT TO SAID SOAP BEING ABOUT 1 TO 3.5 BY WEIGHT, BETWEEN ABOUT ONE PERCENT AND ABOUT FIVE PERCENT BY WEIGHT OF SAID BASE OF TERPINEOL, THE REMAINDER OF SAID BASE BEING SUBSTANTIALLY WATER, SAID BASE HAVING LESS THAN 0.05 PERCENT BY WEIGHT OF FREE ALKALINE MATTER CALCULATED AS POTASSIUM HYDROXIDE. 